Photochromic naphthopyrans

ABSTRACT

Described are novel reversible photochromic naphthopyran compounds substituted on the naphthyl portion at the carbon atom juxtaposed to the oxygen of the pyran ring with, for example, an acetoxy group. Also described are organic host materials that contain or that are coated with such compounds. Articles such as ophthalmic lenses or other plastic transparencies that incorporate the novel naphthopyran compounds or combinations thereof with complementary photochromic compounds, e.g., spiro(indolino)-oxazine type compounds, are also described.

DESCRIPTION OF THE INVENTION

The present invention relates to certain novel naphthopyran compounds.More particularly, this invention relates to novel photochromicnaphthopyran compounds, and to compositions and articles containing suchnovel naphthopyran compounds. When exposed to light radiation involvingultraviolet rays, such as the ultraviolet radiation in sunlight or thelight of a mercury lamp, many photochromic compounds exhibit areversible change in color. When the ultraviolet radiation isdiscontinued, the photochromic compound will return to its originalcolor or colorless state.

Various classes of photochromic compounds have been synthesized andsuggested for use in applications in which a sunlight-induced reversiblecolor change or darkening is desired. U.S. Pat. No. 3,567,605 (Becker)describes a series of pyran derivatives, including certain benzopyransand naphthopyrans. These compounds are described as derivatives ofchromene and are reported to undergo a color change, e.g., fromcolorless to yellow-orange, on irradiation by ultraviolet light attemperatures below about -40° C. Irradiation of the compounds withvisible light or upon raising the temperature to within the range of-10° C. to 0° C. is reported to reverse the coloration to a colorlessstate. U.S. Pat. No. 4,931,221 describes a series of spiropyrans inwhich two cyclopropyl groups are appended to the position adjacent tothe oxygen in the pyran ring. U.S. Pat. No. 4,563,458 describes certain2H-chromenes as precursors of certain chroman-4-aldehydes, which arereacted with certain amines to prepare 4-aminomethylene-chromans and-chromenes that are used in medicaments.

European Patent Publication 246,114 and U.S. Pat. No. 4,826,977 describea series of photochromic spiropyrans in which a spiro-adamantane groupis appended to the position adjacent to the oxygen in the pyran ring.U.S. Pat. No. 4,818,096 and European Patent Publication 250,193 describephotoreactive plastic lenses that are coated or impregnated with thephotochromic spiropyrans of European Patent Publication 246,114 incombination with a blue photochromic benzopyran or naphthopyran havingan aminophenyl substituent at the position adjacent to the oxygen in thepyran ring. European Patent Publication 294,056 describes a process forproducing a polyurethane plastic having photochromic properties.Reversible cleavage photochromic compounds disclosed therein include anaphthopyran derivative in which the pyran ring is substituted at the3-position of the pyran ring with di(p-methoxyphenyl) substituents.Japanese Patent Publication HEI 2(1990)-69471 describes spiropyrancompounds in which a norbornylidene group is substituted at the positionadjacent to the oxygen in the pyran ring.

Padwa et al in J. Org. Chem., Volume 40, No. 8, 1975, page 1142,describes the investigation of photochemical reactions of2,2-dimethylbenzopyran and related compounds, identifies the by-productsand suggests pathways to the ring-opened color intermediates and thefinal non-colored phenolics. The color forms examined by the authors arereported as being unstable at room temperature. The authors do notsuggest ways in which the stability of the examined compounds might beimproved, nor any modification that might be made to the structure ofthe known pyran compounds.

The present invention relates to novel reversible photochromicnaphthopyran compounds containing certain substituents on the naphthoportion of the naphthopyran at a carbon atom that is juxtaposed to theoxygen of the pyran ring. The absorption maxima of these compounds havebeen found to be higher than the corresponding unsubstituted compounds.

DETAILED DESCRIPTION OF THE INVENTION

In recent years, photochromic plastic materials, particularly plasticmaterials for optical applications, have been the subject ofconsiderable attention. In particular, photochromic ophthalmic plasticlenses have been investigated because of the weight advantage theyoffer, vis-a-vis, glass lenses. Moreover, photochromic transparenciesfor vehicles, such as cars and airplanes have been of interest becauseof the potential safety features that such transparencies offer.

Ideal photochromic compounds for use in optical applications, such asconventional ophthalmic lenses, are those which possess (a) a highquantum efficiency for coloring in the near ultraviolet, (b) a lowquantum yield for bleaching with visible light and (c) a relatively fastthermal fade at ambient temperature but not so rapid a thermal fade ratethat the combination of visible light bleaching and thermal fade preventcoloring by the ultraviolet component of strong sunlight.

Compounds, such as 3,3-diphenyl-3H-naphtho[2,1-b]pyran, change color onexposure to the near ultraviolet; but, at room temperature and above,this compound bleaches too rapidly for use in an ophthalmic lens. Thecompound, 2,2-diphenyl-2H-naphtho[1,2-b] pyrin, also colors on exposureto near ultraviolet light at room temperature but does not bleach in areasonable period of time.

In accordance with the present invention, there has been discoveredcertain novel reversible photochromic naphthopyran compounds. Thesecompounds are substituted on the naphthyl portion at the carbon atomjuxtaposed to the oxygen of the pyrin ring and exhibit a bathochromicshift of their absorption maximum without a loss of color intensity. Inparticular, 3,3-diaryl-3H-naphtho[2,1-b] pyrans (Graphic Formula I) thatare appropriately substituted at the number five carbon atom have a highquantum efficiency for coloring in the near ultraviolet and anacceptable rate of fade and may be used in ophthalmic applications.

Naphthopyran compounds contemplated to be within the scope of thepresent invention may be represented by the following graphic formula I:##STR1## L in graphic formula I is the group, --W--T(Z)=Xg, wherein

(1) W is selected from bivalent radicals of the group consisting ofoxygen, carbon, nitrogen, oxygen-carbon, carbon-oxygen, carbon-nitrogen,nitrogen-carbon, and carbon-sulfur, as exemplified respectively by thefollowing graphic formulae L-1 through L-8: ##STR2## wherein J and J'are in each of the formulae L-1 to L-8 independently selected from thegroup consisting of hydrogen and C₁ -C₄ alkyl, e.g., methyl, ethyl,propyl and butyl, or J and J' taken together is a single oxygen, e.g.,--C(O)-- (such as in formula L-2) or --O--C(O)-- (such as in formulaL-4);

(2) T is selected from group consisting of carbon and sulfur, and bearsa partial positive charge;

(3) X is selected from the group consisting of oxygen, sulfur and--N--J", wherein J" is hydrogen, hydroxy, C₁ -C₄ alkyl, C₁ -C₄ alkoxy,or C₁ -C₄ alkenyl, or when J" is C₁ -C₄ alkyl or C₁ -C₄ alkenyl, J" maycombine with Z to form a nitrogen-containing heterocyclic ring;

(4) Z is selected from the group consisting of hydrogen, C₁ -C₄ alkyl,C₁ -C₄ alkenyl, C₁ -C₄ monohaloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, amino,C₁ -C₄ mono- or dialkylamino, i.e., --N(J)J', the unsubstituted andsubstituted aryl groups, phenyl and naphthyl, and the unsubstituted andsubstituted heterocyclic groups, pyridyl, thienyl, furyl, piperidinyl,and furfuryl. The aryl and heterocyclic group substituents may beselected from the group consisting of C₁ -C₄ alkyl, C₁ -C₄monohaloalkyl, C₁ -C₄ polyhaloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₁ -C₄alkoxy, and halogen. The halogen (or halo groups in the haloalkyl)substituent may be fluorine or chlorine;

(5) g is the integer 1 or 2 when X is sulfur, and is the integer 1 whenX is oxygen or --N--J".

Preferably W is oxygen, carbon, or nitrogen (as represented by thegraphic formulae L-1 through L-3, more preferably oxygen; T is carbon; Xis oxygen; Z is C₁ -C₄ alkyl, e.g., methyl, phenyl, or C₁ -C₄monoalkylamino, e.g., methylamino (CH₃ NH--); and g is the integer one(1). More preferably, the group L is acetoxy (CH₃ C(O)O--), benzoyloxy(C₆ H₅ C(O)O--), or methyl carbamyloxy (CH₃ NHC(O)O--).

In graphic formula I, B and B' are each selected from the unsubstitutedand mono, di or poly substituted aryl groups, phenyl and naphthyl,preferably mono- or di-substituted phenyl or naphthyl; the substitutedor unsubstituted heterocyclic groups, pyridyl, thienyl, furyl,piperidinyl, and furfuryl; C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, e.g., (chloroor fluoro) C₁ -C₄ alkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₃ -C₆ cycloalkyl,C₁ -C₄ alkoxy(C₃ --C₆)cycloalkyl, halo(chloro or fluoro) C₃ -C₆cycloalkyl, or B and B' may combine and taken together formadamantylidene.

The substituents for the aryl groups representing B and B' may be C₁ -C₄alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, andhalogen. The halogen (or halo group in the haloalkyl) may be chlorine orfluorine. Phenyl substituents may be located at the ortho, meta, and/orpara positions. Typically, the phenyl substituent contains less than 3substituents, i.e., zero (none), one or two substituents.

Substituents for the heterocyclic groups representing B and B' may be C₁-C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl,or halogen. The halogen (or halo group in the haloalkyl) may be chlorineor fluorine.

Preferably B and B' are each phenyl or substituted phenyl, e g., mono-or di-(C₁ -C₄)alkyl phenyl, such as methylphenyl; mono- or di-(C₁-C₄)alkoxyphenyl, such as methoxyphenyl; chlorophenyl and fluorophenyl.

Compounds represented by graphic formulae I may be prepared by varioussynthetic routes. The particular route chosen will depend on thecomposition of "W". For example, compounds wherein "W" is oxygen (--O--)or oxygen-carbon (--O--C(J)J'), i.e., graphic formulae L-1 and L-4 maybe prepared by reaction of 2,3-dihydroxynaphthalene with an appropriatereagent, e.g, acetic anhydride or an active halogen compound such aschloroacetone, which will yield the corresponding L-substituted hydroxynaphthalene e.g., 3-acetoxy-2-hydroxy naphthalene. The intermediate3-substituted-2-hydroxy naphthalene may then be reacted further with theappropriate disubstituted, i.e., B,B'-substituted, propargyl alcohol,e.g., 1,1-diphenyl-2-propyn-1-ol, under acidic conditions to formcompounds of graphic formula I.

In like manner, compounds wherein "W" corresponds to graphic formulaeL-2, L-5, L-6 and L-8 may be prepared starting with3-hydroxy-2-naphthoic acid. For example, the acid or corresponding acidester may be reduced by several conventional methods to thecorresponding 3-hydroxy-2-naphthaldehyde for conversion via the imine to3(2-hydroxy) naphthylmethylamine. The acid ester can be reduced furtherwith stronger reducing agents, for example, lithium aluminum hydride, to3(2-hydroxy)naphthylmethanol. Both of these intermediates may besequentially converted to the pyran by reaction first with a reagentsuch as a carboxylic acid anhydride or an alkylsulfonyl halide followedby reaction with a B,B'-substituted propargyl alcohol, as describedabove.

Compounds wherein "W" corresponds to graphic formulae L-3 and L-7 may beprepared by first selectively reacting the nitrogen of3-amino-2-naphthol with reagents such as substituted or unsubstitutedbenzoyl halides, alkyl or aryl isocyanates, or active halogen bearingheterocycles, such as chloropyridine, to form 3-substituted-2-naphthols.These intermediates are converted via reaction with a propargyl alcoholto the corresponding pyran.

Compounds represented by graphic formula I may be used in thoseapplications in which organic photochromic substances may be employed,such as for example optical lenses, e.g., ophthalmic and plano lenses,face shields, goggles, visors, camera lenses, windows, automotivewindshields, aircraft and automotive transparencies, e.g., T-roofs,sidelights and backlights, plastic films and sheets, textiles andcoatings, e.g., in coating compositions such as paints. Naphthopyransrepresented by graphic formula I exhibit color changes from colorless tocolors ranging from yellow to orange.

Of particular current interest are the following naphthopyrans:

(1)5-acetoxy-3(3,4-dimethoxyphenyl),3(2-fluorophenyl)-3H-naphtho[2,1-b]pyran,

(2)5-methylcarbamoyloxy-3(3,4-dimethoxyphenyl),3(2-fluorophenyl)-3H-naphtho[2,1-b]pyran,

(3) 5-acetoxy-3,(4-methoxyphenyl),3(2-fluorophenyl)-3H-naphtho[2,1-b]pyran,

(4) 5-acetoxy-3(3,4-dimethoxyphenyl)-3-phenyl-3H-naphtho[2,1-b]-pyran,and

(5) 5-acetoxy-3,3(4-methylphenyl)-3H-naphtho[2,1-b]pyran.

Naphthopyrans described herein may be dissolved in common organicsolvents such as benzene, toluene, chloroform, ethyl acetate, methylethyl ketone, acetone, ethyl alcohol, methyl alcohol, acetonitrile,tetrahydrofuran, dioxane, methyl ether of ethylene glycol,dimethylformamide, dimethylsulfoxide, morpholine and ethylene glycol.They may also be dispersed in fluorocarbons and in liquids containingwater and/or alcohols.

The aforedescribed naphthopyran compounds may also be dissolved insolutions prepared with transparent organic host materials, e.g.,transparent polymers (homopolymers or copolymers) or blends of suchtransparent polymers and optionally a suitable organic solvent, e.g.,transparent polymers dissolved in one or more of the aforedescribedorganic solvents. Examples of such solutions include a poly(vinylacetate)-acetone solution, a nitrocellulose-acetonitrile solution, apoly(vinyl chloride)-methyl ethyl ketone solution, apoly(methylmethacrylate)-acetone solution, a celluloseacetate-dimethylformamide solution, a poly(vinyl pyrrolidone)-acetonitrile solution, a polystyrene-benzene solution and an ethylcellulose-methylene chloride solution. The aforesaid photochromicsolutions or compositions may be applied to a compatible host material,e.g., a transparent support, such as cellulose triacetate, polyethyleneterephthalate or baryta paper and dried to obtain an article that willcolor on exposure to ultraviolet radiation and that will return to itsoriginal state by removing the source of ultraviolet radiation.

The naphthopyran compounds described herein (or compositions containingthem) may be applied to or incorporated also within a coatingcomposition applied to a compatible support; or applied to orincorporated within the article comprising the compatible host, e.g., apolymerized organic material such as a synthetic polymeric plastic hostmaterial.

The naphthopyrans described hereinabove may be incorporated in syntheticplastic materials customarily used for plastic optical lenses, bothplano and ophthalmic. e.g., materials such as methyl methacrylate,polycarbonates and polymerizates prepared from CR-39® diallyl glycolcarbonate monomer. Photochromic materials for photoreactive lensespreferably have the following stated desirable properties; namely, (a) ahigh quantum efficiency for coloring in the near ultraviolet, (b) a lowquantum yield for bleaching with visible light, and (c) a relativelyfast thermal fade at ambient temperatures, but not so fast that thephotochromic material does not color in unfiltered sunlight at ambienttemperatures. In addition, the aforesaid properties are desirablyretained in conventional rigid synthetic plastic materials customarilyused for ophthalmic and plano lenses when such materials have applied toor incorporated therein such naphthopyran compounds.

On irradiation of the compounds of graphic formula I with ultravioletlight, the naphthopyran ring opens reversibly at the carbon-oxygen bondbetween the number 3-carbon atom and the ring oxygen. The formation ofthe open form of the colorless compound is believed to be responsiblefor the coloring observed on exposure to ultraviolet light. The coloredform of the photochromic compounds of graphic formula I will fade to thecolorless state at normal ambient temperatures when not exposed toultraviolet light.

Commercially available photoreactive inorganic glass ophthalmic lensescontaining silver halide particles darken to a gray or brown color insunlight. In order to duplicate this color change in a plastic lensusing the organic photochromic naphthopyrans of graphic formula I, it iscontemplated that such naphthopyrans be used in combination with otherappropriate complementary organic photochromic materials so thattogether they produce the desired near neutral gray or brown color shadewhen the plastic lens containing such photochromic materials are exposedto ultraviolet light. For example, a compound which colors to yellow maybe blended with a compound that colors to an appropriate purple toproduce a brown shade. Similarly, a compound which is orange in itscolored state will produce a shade of gray when used in conjunction withan appropriate blue coloring compound. The aforesaid describedcombination of photochromic materials may be used also in applicationsother than ophthalmic lenses.

Spiro(indolino) pyrido benzoxazine photochromic compounds described inU.S. Pat. No. 4,637,698 and spiro(indolino) naphthoxazines described inU.S. Pat. Nos. 3,562,172, 3,578,602, 4,215,010 and 4,342,668 arereported to color to colors ranging from purple to blue when activated,and these compounds may be used in admixture with or in conjunction withthe yellow-orange novel naphthopyran photochromic compounds described inthis application to obtain a near gray color when exposed to unfilteredsunlight. In addition, certain spiro(indolino)benzoxazines described inU.S. Pat. No. 4,816,584 color to shades of purple/blue when activated,and these compounds may be used also in admixture with or in conjunctionwith the photochromic naphthopyrans described in this application.

The aforesaid first mentioned spiro(indolino)-type compounds may berepresented by the following graphic formula: ##STR3## In the abovegraphic formula II, R₁ may be selected from the group consisting of C₁-C₈ alkyl, e.g., methyl, ethyl, n-propyl, isopropyl, butyl, etc.,phenyl, phen(C₁ -C4)alkyl, e.g., benzyl, naphth(C₁ -C₄)alkyl, e.g.,1-naphthylmethyl, allyl, acrylyl(C₂ -C₆)alkyl, methacrylyl- (C₂-C₆)alkyl, carboxy(C₂ -C₆)alkyl, e.g., β-carboxyethyl, γ-carboxypropyl,δ-carboxybutyl, cyano(C₂ -C₆)alkyl, e.g., β-cyanoethyl, γ-cyanopropyl,β-cyanoisopropyl, and δ-cyanobutyl, C₁ -C₄ acyloxy(C₂ -C₆)alkyl, i.e.,[R_(c) C(O)OR_(d) ⁻⁻, wherein R_(c) is a C₁ -C₄ alkyl and R_(d) is a C₂-C₆ alkyl], e.g., acetoxyethyl, acetoxypropyl, propionyloxyethyl,acetoxybutyl, and propionyloxypropyl, hydroxy(C₂ -C₆)alkyl, e.g.,hydroxyethyl, hydroxypropyl and hydroxybutyl, (C₂ H₄ O)_(m) . CH₃,wherein m is a number of from 1 to 6, and mono- and disubstitutedphenyl, said phenyl substituents being selected from C₁ -C₄ alkyl and C₁-C₅ alkoxy, e.g., methoxy, ethoxy, propoxy, butoxy and pentoxy.Preferably, R₁ is selected from the group consisting of C₁ -C₄ alkyl,phenyl, benzyl, 1-naphth(C₁ -C₂)alkyl, such as 1-naphthylmethyl,carboxy(C₂ -C₄)alkyl, cyano(C₂ -C₄)alkyl, C₁ -C₄ acyloxy(C₂ -C₄)alkyl,e.g., C.sub. 1 -C₄ acyloxyethyl, hydroxy(C₂ -C₄)alkyl, and (C₂ H₄ O)_(m). CH₃, wherein m is a number of from 1 to 3, e.g., 2.

R₂ and R₃ of the above graphic formula II may each be selected from thegroup consisting of C₁ -C₅ alkyl, phenyl, mono- and disubstitutedphenyl, benzyl, or R₂ and R₃ may combine to form a cyclic ring selectedfrom the group consisting of an alicyclic ring containing from 6 to 8carbon atoms (including the spiro carbon atom), norbornyl and adamantyl.The aforesaid phenyl substituents may be selected from C₁ -C₄ alkyl andC₁ -C₅ alkoxy radicals. More particularly, R₂ and R₃ are each selectedfrom C₁ -C₅ alkyl, e.g., methyl, ethyl, propyl, butyl and pentyl, andphenyl. When one of R₂ or R₃ is a tertiary alkyl radical, such astertiary butyl or tertiary amyl, the other is preferably an alkylradical other than a tertiary alkyl radical.

Y in graphic formula II may be carbon or nitrogen. The number and typeof non-hydrogen substituent groups represented by R₄ will vary dependingupon whether Y is carbon or nitrogen. Generally, when Y is carbon eachR₄ substituent may be selected from the group consisting of halogen,e.g., chloro, fluoro, or bromo, C₁ -C₅ alkyl, C₁ -C₅ alkoxy, e.g.,methoxy, ethoxy, propoxy, butoxy and pentoxy, nitro, cyano, thiocyano,C₁ -C₄ monohaloalkyl, e.g., C₁ -C₄ monochloroalkyl, such as chloromethyland chloroethyl, C₁ -C₂ polyhaloalkyl, as, for example, trihaloalkylsuch as trichloroalkyl or trifluoroalkyl, e.g., trifluoromethyl and2,2,2-trifluoroethyl, and monoalkylamino or dialkylamino wherein thealkyl moiety of the alkylamino group contains from one to four carbonatoms, e.g., methylamino, ethylamino, propylamino, dimethylamino anddiethylamino.

The letter "e" in graphic formula II is an integer of from 0 to 2, e.g.,1, and denotes the number of non-hydrogen R₄ substituents. Inparticular, when "e" is 1 or 2 and Y is carbon, each R₄ substituent maybe selected from the group C₁ -C₂ alkyl, C₁ -C₂ alkoxy, chloro, fluoro,bromo, nitro, and trifluormethyl. When "e" is 0 (zero), there are no R₄substituents and all of the aromatic carbon atoms in the naphtho grouphave their full complement of hydrogen atoms for the aromatic groupshown.

When Y is nitrogen, each R₄ (non-hydrogen) substituent may be selectedfrom C₁ -C₅ alkyl, e.g., C₁ -C₂ alkyl, C₁ -C₅ alkoxy, e.g., C₁ -C₂alkoxy, and halogen, e.g., chloro, fluoro or bromo. Typically, "e" is 0(zero) when Y is nitrogen and thus there are no R₄ substituents.

Each R₁₁ in graphic formula II may be selected from C₁ -C₅ alkyl,halogen, C₁ -C₅ alkoxy, nitro, cyano, C₁ -C₄ monohaloalkyl, C₁ -C₄polyhaloalkyl, C₁ -C₈ alkoxycarbonyl, and C₁ -C₄ acyloxy, i.e., R_(c)C(O)O--, wherein R_(c) is a C₁ -C₄ alkyl, e.g., methyl. The letter "d"in graphic formula II represents an integer that may vary from 0 to 4,e.g., 0 to 2, such as 1 or 2, and denotes the number of non-hydrogensubstituents. When "d" is 0 (zero), there are no R₁₁ substituents andall of the aromatic carbon atoms have their full complement of hydrogenatoms for the indole group.

More particularly, spiro(indolino) pyridobenzoxazines (when Y isnitrogen) may be represented by the following graphic formula: ##STR4##

In graphic formula III, R₁, R₂ and R₃ are the same as defined withrespect to graphic formula II. Each R₄ may be selected from C₁ -C₅alkyl, e.g., C₁ -C₂ alkyl, C₁ -C₅ alkoxy, e.g., C₁ -C₂ alkoxy andhalogen, e.g., chloro, fluoro or bromo. The letter "e" may be 0 or 1.Commonly, "e" is 0, and thus, there are no R₄ ' substituents. When "e"is 1, the R₄ substituent may be located on any of the available carbonatoms of the pyrido moiety of the pyrido benzoxazine portion of thecompound, i.e., at the 5', 6', 8' 9' or 10' positions, most usually atthe 8', 9' or 10' positions.

Each R₁₁ ' in graphic formula III may be selected from the groupconsisting of C₁ -C₅ alkyl, e.g., methyl, ethyl, propyl, butyl andpentyl, halogen, e.g., chloro and fluoro, C₁ -C₅ alkoxy, e.g., methoxy,ethoxy, propoxy, butoxy and pentoxy, nitro, cyano, C₁ -C₄ monohaloalkyl,e.g., chloromethyl, fluoromethyl, chloroethyl, chloropropyl, etc., C₁-C₄ polyhaloalkyl, e.g., trihaloalkyl, C₁ -C₈ alkoxycarbonyl, and C₁ -C₄acyloxy, i.e., R_(c) C(O)O--, wherein R_(c) is a C₁ -C₄ alkyl, e.g.,methyl. An example of an acyloxy group is acetoxy. While any halogen,i.e., chlorine, bromine, iodine and fluorine may be used in respect tothe aforesaid halogen or haloalkyl substituents, chlorine, fluorine andbromine, particularly chlorine and fluorine, are preferred for thehalogen substituent and fluorine is preferred for the polyhaloalkylsubstituent, e.g., trifluoromethyl, (CF₃). Preferably, R₁₁ ' is selectedfrom the group consisting of C₁ -C₂ alkyl, chlorine, fluorine, C₁ -C₂trihaloalkyl, e.g., trihalomethyl such as trifluoromethyl and C₁ -C₅alkoxy.

The letter "d" in graphic formula III is an integer from 0 to 4, e.g., 0to 2, such as 1 or 2. When "d" is 2 or more, each R₁₁ ' substituent maybe the same or different and in either case, are selected from theaforedescribed group. The R₁₁ ' substituent(s) may be located on any ofthe available carbon atoms of the benzene ring of the indolino portionof the compound, i.e., at the 4, 5, 6 or 7 positions.

It is possible that photochromic organic substances of graphic formulaIII (and IV) may be a mixture of isomers due to the alternativedirectional mechanism by which intramolecular condensation occurs duringformation of the starting indole reactant (Fischer's base). Indolizationof 3-substituted phenylhydrazones can give rise to a 4-substitutedindole, a 6-substituted indole, or mixtures thereof. Thus, when "d" is1, the photochromic substance may be substituted at the 4 position onthe indoline ring, at the 6 position of that ring or comprise a mixtureof such isomers. When "d" is 2, the R₁₁ ' substituents may be present atany combination of the 4, 5, 6, or 7 carbon atoms of the indoline ringand may comprise an isomeric mixture of such compounds, e.g., a mixtureof compounds having substituents at the 4 and 5, 4 and 6, 5 and 6, 4 and7, 5 and 7, and 6 and 7 positions of the indoline ring. Commonly, when"d" is 2 the R₁₁ ' substituents are located at the 4 and 5, or 5 and 6positions. Also contemplated are materials containing mixtures of suchisomers, e.g., materials comprising 4 (and 6) and 5-substitutedspiro(indolino) pyrido benzoxazines.

Non-limiting examples of spiro(indolino) pyridobenzoxazines of graphicformula III are described in Table 1. Such pyridobenzoxazines are thosein which R₁, R₂, R₃, and R₁₁ ' are as indicated in Table 1, the letter"e" is 0 (zero), and the letter "d" is 0, 1 or 2. A hyphen (-) indicatesthe absence of a non-hydrogen substituent.

                  TABLE 1                                                         ______________________________________                                        Compound/                                                                              R.sub.1 R.sub.2  R.sub.3                                                                             R.sub.11 '                                                                            R.sub.11 '                            ______________________________________                                        1        CH.sub.3                                                                              CH.sub.3 CH.sub.3                                                                            --      --                                    2        CH.sub.3                                                                              CH.sub.3 CH.sub.3                                                                            4(6)-CH.sub.3                                                                         5-CH.sub.3                            3        CH.sub.3                                                                              CH.sub.3 CH.sub.3                                                                            5-OCH.sub.3                                                                           --                                    4        CH.sub.3                                                                              CH.sub.3 CH.sub.3                                                                            5-Cl    6-CH.sub.3                            5        CH.sub.3                                                                              CH.sub.3 C.sub.2 H.sub.5                                                                     --      --                                    6        CH.sub.3                                                                              CH.sub.3 C.sub.2 H.sub.5                                                                     5-CH.sub.3                                                                            4(6)-CH.sub.3                         7        CH.sub.3                                                                              C.sub.2 H.sub.5                                                                        C.sub.2 H.sub.5                                                                     --      --                                    8        n-C.sub.4 H.sub.9                                                                     CH.sub.3 C.sub.2 H.sub.5                                                                     --      --                                    9        CH.sub.3                                                                              CH.sub.3 phenyl                                                                              --      --                                    10       CH.sub.3                                                                              phenyl   phenyl                                                                              --      --                                    11       C.sub.2 H.sub.5                                                                       CH.sub.3 C.sub.2 H.sub.5                                                                     4(6)-CH.sub.3                                                                         5-CH.sub.3                            12       n-C.sub.4 H.sub.9                                                                     CH.sub.3 C.sub.2 H.sub.5                                                                     5-CH.sub.3                                                                            (4)6-CH.sub.3                         13       CH.sub.3                                                                              CH.sub.3 CH.sub.3                                                                            5-CH.sub.3                                                                            (4)6-CH.sub.3                         14       n-C.sub.3 H.sub.7                                                                     CH.sub.3 CH.sub.3                                                                            5-CH.sub.3                                                                            --                                    15       i-C.sub.3 H.sub.7                                                                     CH.sub.3 CH.sub.3                                                                            5-OCH.sub.3                                                                           --                                    16       n-C.sub.3 H.sub.7                                                                     CH.sub.3 CH.sub.3                                                                            4(6)-CH.sub.3                                                                         5-CH.sub.3                            ______________________________________                                    

Compound 2 in Table 1 may be named 1,3,3,4(and6),5-pentamethylspiro-[indolino-2,3' [3H]pyrido [3,2-f][1,4]benzoxazine]. Similarly, compound 6 in Table 1 may be named1,3,4(and 6),5-tetramethyl-3-ethylspiro- [indolino-2,3' [3H] pyrido[3,2-f] [1,4]benzoxazine]. Other compounds in Table 1 may be similarlynamed taking into account the different substituents. Moreover,compounds derived from the description of graphic formula III may besimilarly named by substituting the substituents described with respectto R₁, R₂, R₃, R₄ ' and R₁₁ ' for those found in the description and inTable 1. When the letter "e" is 1 or more, the R₄ ' substituent(s) aregiven a prime (') designation. For nomenclature purposes, numbering ofthe pyrido benzoxazine portion of the molecule is counter clockwisestarting with the nitrogen atom of the oxazine ring as the number 1'position. Numbering of the indolino portion of the molecule is counterclockwise starting with the nitrogen atom as the number 1 position.

Spiro(indolino)naphthoxazines that may be used in the practice of thepresent process may be represented by the following graphic formula:##STR5## wherein R₁, R₂ and R₃ are the same as that described withrespect to graphic formula II.

Each R₄ " substituent in graphic formula IV may be selected from thegroup consisting of halogen, e.g., chloro, fluoro, or bromo, C₁ -C₅alkyl, C₁ -C₅ alkoxy (e.g., methoxy, ethoxy, propoxy, butoxy andpentoxy), nitro, cyano, thiocyano, C₁ -C₄ monohaloalkyl, e.g., C₁ -C₄monochloroalkyl, such as chloromethyl and chloroethyl, C₁ -C₂polyhaloalkyl, as for example, trihaloalkyl, such as trichloroalkyl ortrifluoroalkyl, e.g., trifluoromethyl and 2,2,2-trifluoroethyl, andmonoalkylamino or dialkylamino, wherein the alkyl moiety of thealkylamino group contains from 1 to 4 carbon atoms, e.g., methylamino,ethylamino, propylamino, dimethylamino and diethylamino. Moreparticularly, the R₄ ' substituent may be selected from the group C₁ -C₂alkyl, C₁ -C₂ alkoxy, chloro, fluoro, bromo, nitro and trifluormethyl.The letter "e" in graphic formula IV is an integer from 0 to 2, e.g., 1or 2, and denotes the number of non-hydrogen R4" substituents. When "e"is 0, there are no R₄ " substituents and all of the aromatic carbonatoms of the naphtho moiety of the molecule represented by formula IVhave their full complement of hydrogen atoms for the naphtho groupshown.

As in the case with graphic formula III, when "e" is 1, the R₄ "substituent may be located on any of the available carbon atoms of thenaphtho moiety of the naphthoxazine portion of the molecule, i.e., atthe 5', 6', 7' 8', 9' or 10' positions. Preferably, the R₄ " substituentis present on the 7', 8' or 9' carbon atoms. When "e" is 2, the R₄ "substituents may be same or different and in either case are selectedfrom the above-described group. When "e" is 2, the R₄ " substituents arecommonly located at the 7' and 9', or 8' and 10' positions. Fornomenclature purposes, numbering of spiro(indolino) naphthoxazines isthe same as that described with regard to the spiro(indolino) pyridobenzoxazines of graphic formula III. R₁₁ " and the letter "d" in graphicformula IV are the same as that described with respect to R₁₁ and d ingraphic formula II.

Non-limiting examples of spiro(indolino) naphthoxazines selected fromthe description of graphic formula IV are described in Table 2. Suchspiro(indolino) naphthoxazines are those in which R₁, R₂, R₃, R₄ " andR₁₁ " are as indicated in Table 2, the letter "d" is 0, 1 or 2 and theletter "e" is 1. As in Table 1, a hyphen (-) indicates the absence of anon-hydrogen substituent. In Table 2, all of the R₄ " substituents areat the 9' carbon position.

                                      TABLE 2                                     __________________________________________________________________________    Compound/                                                                            R.sub.1                                                                           R.sub.2                                                                              R.sub.3                                                                              R.sub.4 " (9'-)                                                                    R.sub.11 "                                                                         R.sub.11 "                                 __________________________________________________________________________    1      CH.sub.3                                                                          CH.sub.3                                                                             CH.sub.3                                                                             OCH.sub.3                                                                          --   --                                         2      CH.sub.3                                                                          CH.sub.3                                                                             CH.sub.3                                                                             OCH.sub.3                                                                          5-CH.sub.3                                                                         (4)6-CH.sub.3                              3      CH.sub.3                                                                          CH.sub.3                                                                             CH.sub.3                                                                             OCH.sub.3                                                                          5-OCH.sub.3                                                                        --                                         4      CH.sub.3                                                                          CH.sub.3                                                                             CH.sub.3                                                                             OCH.sub.3                                                                          5-Cl (4)6-CH.sub.3                              5      CH.sub.3                                                                          CH.sub.3                                                                             C.sub.2 H.sub.5                                                                      OCH.sub.3                                                                          --   --                                         6      CH.sub.3                                                                          CH.sub.3                                                                             C.sub.2 H.sub.5                                                                      OCH.sub.3                                                                          5-CH.sub.3                                                                         (4)6-CH.sub.3                              7      CH.sub.3                                                                          C.sub.2 H.sub.5                                                                      C.sub.2 H.sub.5                                                                      OCH.sub.3                                                                          --   --                                         8      n-C.sub.4 H.sub.9                                                                 CH.sub.3                                                                             C.sub.2 H.sub.5                                                                      OCH.sub.3                                                                          --   --                                         9      CH.sub.3                                                                          CH.sub.3                                                                             phenyl OCH.sub.3                                                                          --   --                                         10     CH.sub.3                                                                          phenyl phenyl OCH.sub.3                                                                          --   --                                         11     CH.sub.3                                                                          p-C.sub.6 H.sub.4 OCH.sub.3                                                          p-C.sub.6 H.sub.4 OCH.sub.3                                                          OCH.sub.3                                                                          --   --                                         12     C.sub. 2 H.sub.5                                                                  CH.sub.3                                                                             C.sub.2 H.sub.5                                                                      OCH.sub.3                                                                          5-CH.sub.3                                                                         --                                         13     n-C.sub.4 H.sub.9                                                                 CH.sub.3                                                                             C.sub.2 H.sub.5                                                                      OCH.sub.3                                                                          5-CH.sub.3                                                                         --                                         __________________________________________________________________________

Compound 2 in Table 2 may be named 1,3,3,4(and6),5-pentamethyl-9'-methoxy-spiro[indolino -2,3' [3H]-naphth[2,1-b][1,4]-oxazine]. Similarly, compound 6 in Table 2 may be named1,3,4 (and 6),5-tetramethyl-3-ethyl-9'-methoxyspiro [indolino-2,3'[3H]-naphth [2,1-b][1,4]-oxazine. Other compounds in Table 2 can besimilarly named taking into account the different substituents.Moreover, compounds derived from the description of graphic formula IVmay be similarly named.

Spiro(indolino) benzoxazines compounds described in U.S. Pat. No.4,816,584 may be represented by the following graphic formula V.##STR6## wherein R₁, R₂, R₃ and d are the same as described with respectto graphic formula II and R₁₂ and R₁₃ are each selected from the groupconsisting of C₁ -C₅ alkyl, e.g., C₁ -C₂ alkyl, C₁ -C₅ alkoxy, e.g., C₁-C₂ alkoxy, preferably methoxy, and h is the integer 1 or 2.

When "h" is 1, the R₁₂ substituent may be located on any of theavailable carbon atoms of the benzene ring of the benzoxazine moiety,i.e., at the 5, 6, 7 or 8 positions. Preferably, the R12 substituent islocated at the number 5, 6, or 7 carbon atom. When "h" is 2, the R₁₂substituents may be the same or different and in either case areselected from the above-described group. When "h" is 2, the R₁₂substituents are desirably located at the 5 and 7 or 6 and 8 positions.

Examples of spiro(indolino)benzoxazines within the scope of graphicformula V are listed in Table 3. Compound 1 may be named:7-methoxy-1',3',3',4' (and 6'), 5'-pentamethylspiro- [2H-1,4-benzoxazine-2,2'-indoline]. Compounds 2-6 may be similarly named as substitutedspiro(indolino) benzoxazines using the substituents described in Table 3for such compounds. Moreover, compounds derived from the description ofgraphic formula V may be similarly named. In naming thespiro(indoline)benzoxazines, the IUPAC rules of organic nomenclaturehave been used. The positions of the indolino portion of the moleculehave been numbered counterclockwise starting with the nitrogen atom asthe number one (1) position, and are identified by a prime number, e.g.,3'. The positions of the benzoxazine portion of the molecule have beennumbered clockwise starting with the oxygen atom as the number one (1)position.

                  TABLE 3                                                         ______________________________________                                        Compound                                                                      No.     R.sub.1                                                                              R.sub.2                                                                              R.sub.3                                                                            R.sub.13                                                                             R.sub.13                                                                           R.sub.12                                                                            R.sub.12                         ______________________________________                                        1       Me     Me     Me   4(6)-Me                                                                              5-Me 7-OMe --                               2       Me     Me     Me   4(6)-Me                                                                              5-Me 7-OMe 5-OMe                            3       Me     Me     Me   5-OMe  --   7-OMe 5-OMe                            4       Me     Me     Me   4(6)-Me                                                                              5-Me 7-OMe 6-Ome                            5       Me     Me     Et   --     --   7-OMe 5-OMe                            6       nBu    Me     Me   --     --   7-OMe 5-OMe                            ______________________________________                                         Key:                                                                          Me = methyl                                                                   nBu = nbutyl                                                                  Et = ethyl                                                                    OMe = methoxy                                                            

The naphthopyran compounds of the present invention may be combined withor used in conjunction with spiro(indolino) pyrido benzoxazine, orspiro(indolino) naphthoxazine compounds in amounts and in a ratio suchthat an organic host material to which the mixture of compounds isapplied or in which they are incorporated exhibits a desired resultantcolor, e.g., a substantially neutral color such as shades of gray orbrown, when activated with unfiltered sunlight, i.e., as near a neutralcolor as possible given the colors of the activated pyran and oxazinephotochromic compounds. The relative amounts of the aforesaid oxazineand pyran compounds used will vary and depend in part upon the relativeintensities of the color of the activated species of such compounds, andthe ultimate color desired. Similarly, the naphthopyran compounds of thepresent invention may be combined with spiro(indolino)benzoxazinecompounds in amounts and in a ratio such that an organic host materialto which the mixture of compounds is applied or in which they areincorporated exhibits a near-brown color. Generally, the mole ratio ofthe aforedescribed spiro(indolino) oxazine compound(s) to the pyrancompound(s) of the present invention will vary from about 1:3 to about3:1, e.g., between about 1:1 and about 2:1.

Photochromic compounds of the present invention, mixtures of suchcompounds with other photochromic compounds, or compositions containingsame (hereinafter "photochromic substances") may be applied to orincorporated into a host material by various methods described in theart. Such methods include dissolving or dispersing the substance withinthe host material, e.g., imbibition of the photochromic substance intothe host material by immersion of the host material in a hot solution ofthe photochromic substance or by thermal transfer; providing thephotochromic substance as a separate layer between adjacent layers ofthe host material, e.g., as a part of a polymer film; and applying thephotochromic substance as part of a coating placed on the surface of thehost material. The term "imbibition" or "imbibe" is intended to mean andinclude permeation of the photochromic substance alone into the hostmaterial, solvent assisted transfer absorption of the photochromicsubstance into a porous polymer, vapor phase transfer, and other suchtransfer mechanisms.

Compatible (chemically and color-wise) tints, i.e., dyes, may be appliedto the host material to achieve a more aesthetic result, for medicalreasons, or for reasons of fashion. The particular dye selected willvary and depend on the aforesaid need and result to be achieved. In oneembodiment, the dye may be selected to complement the color resultingfrom the activated photochromic substances, e.g., to achieve a moreneutral color or absorb a particular wavelength of incident light. Inanother embodiment, the dye may be selected to provide a desired hue tothe host matrix when the photochromic substances is in an unactivatedstate.

Adjuvant materials may also be incorporated into the host material withthe photochromic substances prior to, simultaneously with or subsequentto application or incorporation of the photochromic substances in thehost material. For example, ultraviolet light absorbers may be admixedwith photochromic substances before their application to the hostmaterial or such absorbers may be superposed, e.g., superimposed, as alayer between the photochromic substance and the incident light.Further, stabilizers may be admixed with the photochromic substancesprior to their application to the host material to improve the lightfatigue resistance of the photochromic substances. Stabilizers, such ashindered amine light stabilizers and singlet oxygen quenchers, e.g., anickel ion complex with an organic ligand, are contemplated. They may beused alone or in combination. Such stabilizers are described in U.S.Pat. No. 4,720,356. Finally, appropriate protective coating(s) may beapplied to the surface of the host material. These may be abrasionresistant coatings and/or coatings that serve as oxygen barriers. Suchcoatings are known in the art.

Singlet oxygen quenchers that may be used as stabilizers includecomplexes of nickel(2+), i.e., Ni²⁺, with an organic ligand, cobalt(III) tris-di-n-butyldithiocarbamate, cobalt (II)diisopropyldithiocarbamate, and nickel diisopropyldithiophosphate. Suchsinglet oxygen quenchers are used in stabilizing amounts.

Preferred are complexes of Ni²⁺ such as[2,2-thiobis[4-(1,1,3,3-tetramethylbutyl) phenolato] (butylamine)]nickel, which is sold under the tradename of CYASORB UV 1084; nickel[O-ethyl(3,5-di-tert-butyl-4-hydroxybenzyl)] phosphonate, which is soldunder the tradename IRGASTAB 2002; nickel dibutyldithiocarbamate, whichis sold under the tradename RYLEX NBC;bis[2,2'-thiobis-4-(1,1,3,3-tetramethylbutyl)phenolato] nickel, which issold under the tradename UV-CHEK AM 101; nickel di-isopropyldithiophosphate and other Ni²⁺ complexes sold under the tradenames ofUV-CHEK AM 105, UV-CHEK 126, and UV-CHEK AM 205.

Hindered amine light stabilizers that may be used includebis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, which is sold under thetradename TINUVIN 770; bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, which is sold under the tradename TINUVIN 765;di(1,2,2,6,6-pentamethyl-4-piperidinyl)butyl(3',5'-ditertiarybutyl-4-hydroxybenzyl)malonate,which is sold under the tradename TINUVIN 144;poly[(6-[(1,1,3,3-tetramethylbutyl)-amino]-1,3,5-triazine-2,4-diyl)-(6-[2,2,6,6-tetramethyl-4-piperidinyl]-amino-hexamethylene)],which is sold under the tradename CHIMASSORB 944; andpoly[[6-(morpholino)-s-triazine-2,4-diyl][16-(2,2,6,6-tetramethyl-4-piperdyl)amino]hexamethylene], which is sold under the tradename CYASORB 3346. Otherhindered amine light stabilizers that may be used are those sold underthe tradename TINUVIN 622, SPINUVEX A-36 and HOSTAVIN TMN 20. Suchstabilizers are used in stabilizing amounts.

The foregoing singlet oxygen quenchers and hindered amine lightstabilizers may be used singly or in combination in amounts sufficientto enhance the light-fatigue resistance of the photochromic substance(s)described herein. Between 0.01 and about 5 percent by weight of theforegoing stabilizers may be used (alone or in combination) to improvethe light fatigue resistance of the photochromic materials.

The polymer host material will usually be transparent, but may betranslucent or even opaque. The polymer product need only be transparentto that portion of the electromagnetic spectrum, which activates thephotochromic substance, i.e., that wavelength of ultraviolet (UV) lightthat produces the open form of the substance and that portion of thevisible spectrum that includes the absorption maximum wavelength of thesubstance in its UV activated form, i.e., the open form. Further, theresin color should not be such that it masks the color of the activatedform of the photochromic substance, i.e., so the change in color isreadily apparent to the observer. Preferably, the host material articleis a solid transparent or optically clear material, e.g., materialssuitable for optical applications, such as plano and ophthalmic lenses,windows, automotive transparencies, e.g., windshields, aircrafttransparencies, plastic sheeting, etc.

Examples of host materials which may be used with the photochromicsubstances or compositions described herein include: polymers, i.e.,homopolymers and copolymers, of polyol(allyl carbonate) monomers,polymers, i.e., homopolymers and copolymers, of polyfunctional acrylatemonomers, polyacrylates, poly(alkylacrylates) such as poly(methylmethacrylate), cellulose acetate, cellulose triacetate, celluloseacetate propionate, cellulose acetate butyrate, poly(vinyl acetate),poly(vinyl alcohol), poly(vinyl chloride), poly(vinylidene chloride),polyurethanes, polycarbonates, poly(ethylene terephthalate),polystyrene, copoly(styrene-methyl methacrylate)copoly(styrene-acrylonitrile), polyvinylbutyral and polymers, i.e.,homopolymers and copolymers, of diallylidene pentaerythritol,particularly copolymers with polyol (allyl carbonate) monomers, e.g.,diethylene glycol bis(allyl carbonate), and acrylate monomers.

Transparent copolymers and blends of transparent polymers are alsosuitable as host materials. Preferably, the host material is anoptically clear polymerized organic material prepared from apolycarbonate resin, such as the carbonate-linked resin derived frombisphenol A and phosgene, which is sold under the trademark, LEXAN; apoly(methyl methacrylate), such as the material sold under thetrademark, PLEXIGLAS; polymerizates of a polyol(allyl carbonate)monomer, especially diethylene glycol bis(allyl carbonate), whichmonomer is sold under the trademark CR-39, and polymerizates ofcopolymers of a polyol (allyl carbonate), e.g., diethylene glycolbis(allyl carbonate), with other copolymerizable monomeric materials,such as copolymers with vinyl acetate, e.g., copolymers of from 80-90percent diethylene glycol bis(allyl carbonate) and 10-20 percent vinylacetate, particularly 80-85 percent of the bis(allyl carbonate) and15-20 percent vinyl acetate, and copolymers with a polyurethan havingterminal diacrylate functionality, as described in U.S. Pat. No.4,360,653; cellulose acetate, cellulose propionate, cellulose butyrate,cellulose acetate butyrate, polystyrene and copolymers of styrene withmethyl methacrylate, vinyl acetate and acrylonitrile.

Polyol (allyl carbonate) monomers which may be polymerized to form atransparent host material are the allyl carbonates of linear or branchedaliphatic or aromatic liquid polyols, e.g., aliphatic glycol bis(allylcarbonate) compounds, or alkylidene bisphenol bis(allyl carbonate)compounds. These monomers can be described as unsaturated polycarbonatesof polyols, e.g, glycols. The monomers can be prepared by procedureswell known in the art, e.g., methods described in U.S. Pat. Nos.2,370,567 and 2,403,113.

The aforedescribed polyol (allyl carbonate) monomers may be representedby the graphic formula: ##STR7## wherein R is the radical derived froman unsaturated alcohol and is commonly an allyl or substituted allylgroup, R' is the radical derived from the polyol, and n is a wholenumber from 2-5, preferably 2. The allyl group (R) may be substituted atthe 2 position with a halogen, most notably chlorine or bromine, or analkyl group containing from 1 to 4 carbon atoms, generally a methyl orethyl group. The R group may be represented by the graphic formula:##STR8## wherein R_(o) is hydrogen, halogen, or a C₁ -C₄ alkyl group.Specific examples of R include the groups: allyl, 2-chloroallyl,2-bromoallyl, 2-fluoroallyl, 2-methylallyl, 2-ethylallyl,2-isopropylallyl, 2-n-propylallyl, and 2-n-butylallyl. Most commonly Ris the allyl group, H₂ C═CH--CH₂ --.

R' is a polyvalent radical derived from the polyol, which can be analiphatic or aromatic polyol that contains 2, 3, 4 or 5 hydroxy groups.Typically, the polyol contains 2 hydroxy groups, i.e., a glycol orbisphenol. The aliphatic polyol can be linear or branched and containfrom 2 to 10 carbon atoms. Commonly, the aliphatic polyol is an alkyleneglycol having from 2 to 4 carbon atoms or a poly(C₂ -C₄) alkyleneglycol, i.e., ethylene glycol, propylene glycol, trimethylene glycol,tetramethylene glycol, or diethylene glycol, triethylene glycol, etc.

The aromatic polyol can be represented by the graphic formula: ##STR9##wherein A is a bivalent radical derived from an acyclic aliphatichydrocarbon, e.g., an alkylene or alkylidene radical, having from 1 to 4carbon atoms, e.g., methylene, ethylene, and dimethylmethylene(isopropylidene), R_(a) represents lower alkyl substituents of from 1 to3 carbon atoms and halogen, e.g., chlorine and bromine, and p is theinteger 0, 1, 2, or 3. Preferably, the hydroxyl group is in the ortho orpara position.

Specific examples of the radical R' include: alkylene groups containingfrom 2 to 10 carbon atoms such as ethylene, (--CH₂ --CH₂ --),trimethylene, methylethylene, tetramethylene, ethylethylene,pentamethylene, hexamethylene, 2-methylhexamethylene, octamethylene, anddecamethylene; alkylene ether groups such as --CH₂ --O--CH₂ --, --CH₂CH₂ --O--CH₂ CH₂ --, --CH₂ --O--CH₂ --CH₂ --, and --CH₂ CH₂ CH₂ --O--CH₂CH₂ CH₂ --; alkylene polyether groups such as --CH₂ CH₂ --O--CH₂ CH₂--O--CH₂ CH₂ --, and --CH₂ CH₂ CH₂ --O--CH₂ CH₂ CH₂ --O--CH₂ CH₂ CH₂ --;alkylene carbonate and alkylene ether carbonate groups such as CH₂ CH₂--O--CO--O--CH₂ CH₂ -- and --CH₂ CH₂ --O--CH₂ CH₂ --O--CO--O--CH₂ CH₂--O--CH₂ CH.sub. 2 --; and isopropylidene bis(para-phenyl), i.e.,##STR10## Most commonly, R' is --CH₂ CH₂ --, --CH₂ CH₂ --O--CH₂ CH₂ --,or --CH₂ CH₂ --O--CH₂ CH₂ --O--CH₂ CH₂ --.

Specific non-limiting examples of polyol (allyl carbonate) monomersinclude ethylene glycol bis(2-chloroallyl carbonate), ethylene glycolbis(allyl carbonate), diethylene glycol bis(2-methallyl carbonate),diethylene glycol bis(allyl carbonate), triethylene glycol bis(allylcarbonate), propylene glycol bis(2-ethylallyl carbonate),1,3-propanediol bis(allyl carbonate), 1,3-butanediol bis(allylcarbonate), 1,4-butanediol bis(2-bromoallyl carbonate), dipropyleneglycol bis(allyl carbonate), trimethylene glycol bis(2-ethylallylcarbonate), pentamethylene glycol bis(allyl carbonate), andisopropylidene bisphenol bis(allyl carbonate).

Industrially important polyol bis(allyl carbonate) monomers which may beutilized in the invention herein contemplated are: ##STR11## Diethyleneglycol bis(allyl carbonate) is preferred.

Because of the process by which the polyol(allyl carbonate) monomer isprepared, i.e., by phosgenation of the polyol (or allyl alcohol) andsubsequent esterification by the allyl alcohol (or polyol), the monomerproduct can contain related monomer species in which the moietyconnecting the allyl carbonate groups contains one or more carbonategroups. These related monomer species can be represented by the graphicformula: ##STR12## wherein R is as defined above, R_(b) is a bivalentradical, e.g., alkylene or phenylene, derived from a diol, and s is awhole number from 2 to 5. The related monomer species of diethyleneglycol bis(allyl carbonate) can be represented by the graphic formula,##STR13## wherein s is a whole number from 2 to 5. The polyol (allylcarbonate) monomer can typically contain from 2 to 20 weight percent ofthe related monomer species and such related monomer species can bepresent as mixtures, i.e., mixtures of the species represented by sbeing equal to 2, 3, 4, etc.

In addition, a partially polymerized form of the polyol (allylcarbonate) monomer, i.e., prepolymer, can be used. In that embodiment,the monomer is thickened by heating or partially polymerized by usingsmall, e.g., 0.5-1.5 parts of initiator per hundred parts of monomer(phm), to provide a non-gel containing, more viscous monomeric material.

As used in the present description and claims, the term polyol(allylcarbonate) monomer or like names, e.g., diethylene glycol bis(allylcarbonate), are intended to mean and include the named monomer orprepolymer and any related monomer species contained therein.

Polyfunctional acrylate monomers that may be used to prepare syntheticpolymeric host materials are esterification Products of an acrylic acidmoiety selected from the group consisting of acrylic acid andmethacrylic acid, and a polyol, e.g., a diol, a triol or tetracarbinol.More particularly, the polyfunctional acrylate monomer may berepresented by the following graphic formula:

    (CH.sub.2 =C(R.sub.t)--C(O))--.sub.n R"                    (XV)

wherein R_(t) is hydrogen or methyl, n is the number 2, 3, or 4, and R"is the multivalent radical, i.e., a bivalent, trivalent or quadravalentradical, remaining after removal of the hydroxy groups from a polyol,having from 2 to 4 hydroxy groups, e.g., a diol, a triol ortetracarbinol respectively. More particularly, R_(t) is hydrogen ormethyl, and n is 2 or 3, more usually 2.

R" may be selected from the group consisting of alpha, omega C₂ -C₈glycols, cyclohexane diol, diethylene glycol, triethylene glycol,tetraethylene glycol, dipropylene glycol, C₂ -C₅ triols andpentaerythritol. Examples of such polyols include ethylene glycol,trimethylene glycol, 1,4-butane diol, 1,5-pentane diol, 1,6-hexane diol,propylene glycol, trimethylol propane, glycerol and the like.

Examples of polyfunctional acrylate monomers, such as diacrylates andtriacrylates, include: ethylene glycol diacrylate, ethylene glycoldimethacrylate, 1,2-propane diol diacrylate, 1,3-propane dioldiacrylate, 1,2-propane diol dimethacrylate, 1,3-propane dioldimethacrylate, 1,4-butane diol diacrylate, 1,3-butane dioldimethacrylate, 1,4-butane diol dimethacrylate, 1,5-pentane dioldiacrylate, 2,5-dimethyl-1,6-hexane diol dimethacrylate, diethyleneglycol diacrylate, diethylene glycol dimethacrylate, triethylene glycoldimethacrylate, trimethylol propane trimethacrylate, tetraethyleneglycol diacrylate, tetraethylene glycol dimethacrylate, dipropyleneglycol diacrylate, dipropylene glycol dimethacrylate, trimethylolpropane triacrylate, glycerol triacrylate, glycerol trimethacrylate,pentaerythritol triacrylate, pentaerythritol dimethacrylate,pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate andmixtures of such acrylate monomers.

A portion of the polyfunctional acrylate monomer may be replaced with amonofunctional copolymerizable monomer containing the vinyl (CH₂ =CH-)grouping. Such compatible monomers include monofunctional acrylic andmethacrylic acid esters, and vinyl esters of C₂ -C₆ carboxylic acids,i.e., vinyl carboxylates. Preferably, the copolymerizable monomer is anon-aromatic, e.g., non-benzenoid, containing monomer. Monofunctionalacrylic or methacrylic ester monomers may be graphically illustrated bythe following formula,

    CH.sub.2 ═C(R.sub.t)--C(O)--O--R'"                     (XVI)

wherein R_(t) is hydrogen or methyl, and R'" is selected from the groupconsisting of C₁ -C₁₂, e.g., C₁ -C₈, alkyl, C₅ -C₆ cycloalkyl, glycidyland hydroxyethyl. Preferably, R'" is a C₁ -C₄ alkyl, e.g., methyl orcyclohexyl.

Examples of monofunctional acrylic acid type monomers include, forexample, the acrylic and methacrylic acid esters of alkanols such asmethanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol andoctanol, e.g., methyl acrylate, methyl methacrylate, ethyl acrylate andethyl methacrylate, cycloalkanols such as cyclopentanol andcyclohexanol, glycidol (3-hydroxy propylene oxide, (d, 1, d1)) andethylene glycol. Examples of vinyl carboxylates include vinyl acetate,vinyl propionate, vinyl butyrate and vinyl valerate. In addition toand/or in place of the aforedescribed monofunctional copolymerizablemonomer, monofunctional allylic and difunctional allylic copolymerizablecompatible monomers may also replace a portion of the polyfunctionalacrylate monomer. Monofunctional allylic monomers contemplated includeallyl esters of C₂ -C₆ carboxylic acids, C₁ -C₆ allyl ethers and othercopolymerizable allyl compounds. Preferably the monofunctional allylicmonomer is a non-aromatic compound. Difunctional allylic copolymerizablemonomers contemplated herein are the polyol (allyl carbonates) monomersof graphic formula VI.

The amount of photochromic substance or composition containing sameapplied to or incorporated into a host material is not critical providedthat a sufficient amount is used to produce a photochromic effectdiscernible to the naked eye upon activation. Generally such amount canbe described as a photochromic amount. The particular amount useddepends often upon the intensity of color desired upon irradiationthereof and upon the method used to incorporate or apply thephotochromic substances. Typically, the more compound applied orincorporated, the greater is the color intensity. Generally, the amountof each photochromic substance incorporated into or applied to the hostmaterial may range from about 0.01 or 0.05 to about 10 to 20 percent byweight. More typically, the amount of photochromic substance(s)incorporated into or applied to the host material will range from about0.01 to about 2 weight percent, more particularly, from about 0.01 toabout 1 weight percent, e.g., from about 0.1 or 0.5 to about 1 weightpercent, based on the weight of the host material.

The present invention is more particularly described in the followingexamples which are intended as illustrative only, since numerousmodifications and variations therein will be apparent to those skilledin the art.

EXAMPLE 1

A reaction flask was charged with 15 milliliters (ml) of methylenechloride and 6.4 grams (0.04 mole) of 2,3-dihydroxynaphthalene. Aceticanhydride (4.0 grams) was added to the reaction flask with stirring. Thereaction flask was cooled with an ice bath and 4.05 ml of triethylaminewere added to the reaction flask over a 5 minute period. The reactionmixture was allowed to set at room temperature for 1.5 hours and thenpoured into dilute aqueous hydrochloric acid. The white solid productthat precipitated was filtered, washed with methylene chlorine to removediacylated material, washed with water, and then dried. The product (6.0grams) was confirmed as 3-acetoxy-2-hydroxynaphthalene by nuclearmagnetic resonance (NMR) spectroscopy.

2.0 grams (g) of the aforedescribed product,3-acetoxy-2-hydroxynaphthalene, were mixed with 2.0 g of1,1-diphenyl-2-propyn-1-ol in 75 ml of benzene. A catalytic amount ofp-toluene sulfonic acid was added and the mixture heated with stirringto 60° C. After 2 hours, the reaction mixture was cooled to roomtemperature, poured into dilute aqueous sodium hydroxide and theresulting benzene phase separated from the aqueous phase. The benzenephase was washed with water, dried over anhydrous sodium sulfate and thebenzene removed on a rotary evaporator. The resultant oil product wasmixed with a hexane-ether mixture to induce crystallization. Theresultant product was filtered, washed with a small amount of hexane,and dried. The product (2.5 grams) melted at 139°-141° C. An NMRspectrum confirmed the product to be5-acetoxy-3,3-diphenyl-3H-naphtho[2,1-b]pyran.

EXAMPLE 2

A reaction flask was charged with 3.2 g (0.02 mole) of2,3-dihydroxynaphthalene and 0.4 mole of 2-chloropyridine and themixture heated at 150° C. for 2 hours. The resultant mixture was cooledand placed in a separatory funnel containing dilute aqueous sodiumhydroxide and methylene chloride. The aqueous phase was made acidic bythe addition of dilute hydrochloric acid and the resultant solution thenmade slightly basic by the addition of aqueous sodium bicarbonate. Thesolid which crystallized from the aqueous solution was washed with hotwater until the starting material (2,3-dihydroxynaphthalene) wasremoved. The remaining solid product (2.5 g) was confirmed to be3(2-pyridyloxy)-2-hydroxynaphthalene by NMR spectroscopy.

The above prepared 3(2-pyridyloxy)-2-hydroxynaphthalene (2.0 g) wasmixed with 75 ml of toluene and 2.0 g of 1,1-diphenyl-2- propyn-1-ol. Amolar equivalent (based on the 3(2-pyridyloxy)-2-hydroxynaphthalenereactant) of p-toluene sulfonic acid (1.6 g) was added to the reactantmixture which was heated to 60° C. with stirring. After 15 minutes, themixture was cooled, poured into dilute aqueous sodium hydroxide and thetoluene layer separated from the aqueous phase. The toluene layer waswashed with water, dried over anhydrous sodium sulfate and the tolueneremoved on a rotary evaporator. The resultant oil product was columnchromatographed on silica using a 1:1 mixture of hexane:chloroform asthe elutant. The photochromic fractions were combined and the materialre-chromatographed on a medium pressure column of reverse phase (RP-8)silica using a 2:1 mixture of acetonitrile:water as the elutant. Thephotochromic fractions were combined, rotovaped to remove acetonitrileand the product extracted into methylene chloride. The methylenechloride was then removed on a rotary evaporator and the resultant oilinduced to crystallize by cooling in a mixture of hexane and diethylether. The product was filtered, washed with a small amount of hexane,and dried. The product (0.8 g) melted at 124°-125.5° C. NMR spectroscopyconfirmed the product to be 5(2-pyridyloxy)-3,3-diphenyl-3Hnaphtho[2,1-b]pyran.

EXAMPLE 3

In accordance with the procedure of Example 1,3-acetoxy-2-hydroxynaphthalene (2.0 g, 0.01 mole) was reacted with1-phenyl-1-p-methoxyphenyl-2-propyn-1-ol (2.4 grams). The product waschromatographed twice over silica using a 2:1 mixture of hexane:ethylacetate as elutant. The product was an oil. The product was confirmed as5-acetoxy-3-phenyl-3-p-methoxy phenyl-3H-naphtho[2,1-b]pyran by NMRspectroscopy.

EXAMPLE 4

A reaction flask was charged with 50 ml of methylene chloride, 6.4 g(0.4 mole) of 2,3-dihydroxynaphthalene and 0.4 mole of benzoyl chloride.The stirred mixture was cooled in an ice bath and a slight excess oftriethylamine added dropwise to the reaction flask. The ice bath wasremoved and the reaction mixture stirred for one hour. Dilutehydrochloric acid (50 ml) was added to the reaction flask and theresultant mixture stirred. A solid precipitated and the contents of thereaction flask were filtered. The filter cake (solid precipitate) waswashed with a small amount of methylene chloride to remove thedi-benzoylated product. The remaining solid product was washed withwater and dried to yield 7.9 g of product, i.e.,3-benzoyloxy-2-hydroxynaphthalene.

12 g of phenyl-p-methoxyphenyl ketone was mixed in 75 ml oftetrahydrofuran at room temperature with a 20 percent excess of sodiumacetylide, which was obtained as an 18 percent solution inxylene/mineral oil. The mixture was allowed to set for 24 hours withstirring while being protected from moisture. Dilute hydrochloric acidwas added to the reaction mixture and the organic layer separated. Theaqueous phase was extracted with ether and the extracts combined, driedand rotovaped. The resultant oil was chromatographed on silica using a2:1 mixture of hexane:ethyl acetate as elutant to yield 9.5 grams of alight yellow oil. NMR spectroscopy confirmed the product to be5-benzyloxy-1-phenyl-1-p-methoxy phenyl-3-propyn-1-ol.

2.8 g of the aforesaid light yellow oil and 3 g of3-benzoyloxy-2-hydroxynaphthalene were mixed in benzene in the presenceof a trace amount of toluene sulfonic acid catalyst. The reactionmixture was heated for 45 minutes at reflux. Subsequently, the reactionmixture was cooled, washed with aqueous sodium hydroxide, and theorganic phase separated from the aqueous phase. The residual oil waschromatographed on silica using a 4:1 mixture of hexane:ethyl acetate aselutant. The photochromic fractions were collected and crystallized froma hexane-ether mixture. The resultant crystals were dried, washed with aslight amount of hexane and dried. The product (2.5 g) was ayellow-white crystal which melted at 125°-126° C. NMR spectroscopyconfirmed the product to be 5-benzoyloxy-3-phenyl-3-p-methoxyphenyl-3H-naphtho[2,1-b]pyran.

EXAMPLE 5

The procedure of Example 4 was repeated using1,1-diphenyl-3-propyn-1-ol. The reaction mixture was heated in benzenewith a small amount of toluene sulfonic catalyst for 1 hour. Thereaction mixture was a dark orange color. The reaction mixture wascooled and the solid reactant that had not dissolved, i.e.,3-benzoyloxy-2-hydroxynaphthalene, removed by filtration. The benzenesolution was washed with 5 percent aqueous sodium hydroxide and thebenzene solvent removed on a rotary evaporator. The residual oil wascolumn chromatographed on silica using a 4:1 hexane:ethyl acetatemixture as the elutant. The photochromic fractions were combined andinduced to crystallize by cooling in a hexane-diethyl ether mixture. Thesolid product was filtered, washed with a little fresh hexane-diethylether and dried. 2.8 g of product was obtained, which was confirmed byNMR spectroscopy to be 5-benzoyloxy-3,3-diphenyl-3H-naphtho[2,1-b]pyran.

EXAMPLE 6

33.5 grams of 2,3-dihydroxynaphthalene was reacted with a molarequivalent (12 g) of methyl isocyanate in methylene chloride in thepresence of a catalytic amount of dimethylaminopyridine (DMAP). Thereaction solution initially exothermed to 40° C. and then was allowed tocool back to room temperature. The reaction solution was then stirredfor one hour. Subsequently, the reaction mixture was filtered to removesolid, which was washed with methylene chloride and then air dried. Theproduct was confirmed by NMR spectroscopy to be3-methylcarbamyloxy-2-hydroxynaphthalene.

Three grams of the product prepared as above was reacted with 2 grams of1,1-diphenyl-2-propyn-1-ol in benzene using p-toluene sulfonic acid asthe catalyst. The reaction mixture was heated to reflux for two hoursand then cooled and washed with dilute aqueous sodium hydroxide. Solidspresent in the reaction mixture were removed by filtration, the aqueousphase separated from the organic phase, and the organic phase rotovapedto remove benzene solvent. The residue was taken up in ether andfiltered to remove more solid. These solids were shown to be thematerial 3-methylcarbamyloxy-2-hydroxynaphthalene. The ether was removedon a rotary evaporator and the resultant solid washed with a 50:50mixture of hexane:diethyl ether to yield 0.75 g of a solid product,which was confirmed by NMR spectroscopy to be5-methylcarbamyloxy-3,3-diphenyl-3H-naphtho[2,1-b]pyran.) The meltingpoint of the product was determined to be 154°-156° C.

EXAMPLE 7

Two grams of 3-methyl carbamyloxy-2-hydroxynaphthalene and 4 grams ofcrude 1-phenyl-1-p-methoxyphenyl-3-propyn-1-ol were suspended in 100 mltoluene. The mixture was refluxed for one hour in the presence of acatalytic amount of p-toluene sulfonic acid. The reaction mixture wascooled and washed with dilute aqueous sodium hydroxide and then withwater. The organic phase was separated and toluene removed on a rotaryevaporator. The remaining crude oil was chromatographed on silica usingas elutants first hexane:ethyl acetate (2:1) and then chloroform:hexane(1:1). The photochromic fractions were combined, crystallized fromdiethyl ether, and the crystals suctioned filtered. The filteredcrystals were washed with diethyl ether. The crystalline product waslight tan in color and had a melting point of 150°-153° C. NMRspectroscopy confirmed the product to be5-methylcarbamyloxy-3-phenyl-3-methoxyphenyl-3H-naphtho[1,2-b]pyran.

EXAMPLE 8

2,3-dihydroxynaphthalene (6.4 g), chloroacetone (0.04 mole, 3.7 g) andanhydrous powdered potassium carbonate (0.04 mole, 5.5 g) were added to150 ml of anhydrous acetone and mixed under reflux for six hours. Themixture was cooled and the acetone removed on a rotary evaporator. Waterwas added and the resultant solid broken up and filtered. The filtercake was washed with hot water to remove any unreacteddihydroxynaphthalene reactant and dried. The dried product (6.8 g) wasidentified by NMR spectroscopy to be a mixture of2-hydroxy-3-(2-oxy)-propoxy naphthalene and2-hydroxy-2-methyl-1,4-naphthodioxan. Two grams of this mixture, 2g of1,1-diphenyl-2-propyn-1-ol, and a catalytic amount of p-toluene sulfonicacid were mixed in 100 ml of toluene. The mixture was refluxed for 2hours, cooled, washed with dilute aqueous sodium hydroxide, andfiltered. The toluene solution was washed twice with water and then thetoluene removed on a rotary evaporator. On addition of diethyl ether,the product crystallized. The product crystals were filtered, washedwith fresh diethyl ether, and dried. The melting point of the crystalswas determined to be 184°-186° C. and NMR spectroscopy confirmed thestructure to be 5-(2-acetonyloxy)-3,3-diphenyl-3H-naphtho[2,1-b]pyran.

EXAMPLE 9

Ten grams of 4,4'-dimethylbenzophenone was added to 100 ml oftetrahydrofuran containing a small amount of lithium aluminum hydride. Aslight excess (14 g) of sodium acetylide as an 18% solution inxylene-mineral oil was added to the ketone and the mixture stirred atroom temperature. After three hours, no ketone was observed in thereaction mixture. Dilute aqueous hydrochloric acid (50 ml) was added tothe reaction mixture and the organic layer separated, then washed withwater, and dried. The aqueous phase was washed with ether and the etherextract washed with water and dried. The organic fractions were combinedand solvent removed on a rotary evaporator to give the crude acetylinicalcohol 1,1-di-p-methylphenyl-3-propyn-1-ol as a light tan oil.

Three grams of the foregoing oil and 2 grams of3-acetoxy-2-hydroxynaphthalene were mixed in benzene and heated toreflux with stirring in the presence of a trace amount of toluenesulfonic acid. The reaction mixture was heated at reflux for one hourafter which the reaction mixture was poured into dilute aqueous sodiumhydroxide. The benzene layer was separated, washed with water andsolvent removed on a rotary evaporator. The resultant product was an oilwhich was column chromatographed on silica using a 2:1 hexane:ethylacetate mixture as elutant. The photochromic fractions were combined andcrystallized from a hexane/ether mixture by cooling in a dry ice-acetonemixture. The crystals were suction filtered and dried. The product wasconfirmed by NMR spectroscopy to be5-acetoxy-3,3-di(p-methylphenyl)-3H-naphtho[2,1-b]pyran. The product hasa melting point of 118°-119° C.

EXAMPLE 10

Chloroacetic anhydride (8.5 g) was reacted with 2,3-dihydroxynaphthalene(8.0 g) in methylene chloride in the presence of triethylamine. Aqueoushydrochloric acid was added to the reaction product to precipitate3-chloroacetoxy-2-hydroxynaphthalene. The product was suction filteredand washed with methylene chloride.

3-chloroacetoxy-2-hydroxynaphthalene (2 g) was mixed with 2 g of1,1-diphenyl-2-propyn-1-ol in benzene and heated to reflux in thepresence of a catalytic amount of p-toluene sulfonic acid. After onehour, the reaction mixture was cooled and poured into dilute aqueoushydrochloric acid. The benzene layer was extracted with aqueous sodiumhydroxide, washed with water and solvent removed on a rotary evaporator.The solid product was washed with a hexane/ether mixture and suctiondried. NMR spectroscopy confirmed the product to be5-chloroacetoxy-3,3-diphenyl-3H-naphtho[2,1-b]pyran. The product (2.1 g)had a melting point of 106°-108° C.

EXAMPLE 11

3-chloroacetoxy-2-hydroxynaphthalene (2 g) were mixed with1,1-di-p-tolyl-2-propyn-1-ol (3 g) in benzene and the mixture heatedslowly to reflux in the presence of a catalytic amount of toluenesulfonic acid. After about one hour, the reaction mixture was cooled,washed sequentially with dilute aqueous sodium hydroxide and water, andthen dried. Benzene was removed on a rotary evaporator to give an oilthat slowly crystallized. The crystals were slurried in a 3:1hexane:ether mixture, filtered, and washed with a small amount of freshhexane:diethyl ether and dried. The resultant product (2.7 g) wasconfirmed by NMR spectroscopy to be 5-chloroacetoxy-3,3-p-methylphenyl-3H-naphtho[2,1-b]pyran. The product had a melting point of 162°-163° C.

EXAMPLE 12

The naphthopyran compounds of Examples 1-11 were imbibed into separatepolymerizates of poly[diethylene glycol bis(allyl carbonate)]. Onexposure to ultraviolet light from a 365 nm lamp, the imbibed polymersamples elicited a photochromic response which faded on removal of theUV light source. The absorption maximums and fade rates of the compoundsof Examples 1-11 are tabulated in Table I.

                  TABLE I                                                         ______________________________________                                        Compound of   Absorption Fade Rate.sup.1.                                     Example       λ Max (NM)                                                                        T 1/2, seconds                                       ______________________________________                                        1             455        81                                                   2             440        94                                                   3             483        63                                                   4             483        210                                                  5             447        138                                                  6             446        100                                                  7             467        82                                                   8             434        96                                                   9             470        134                                                  10            458        96                                                   11            476        105                                                  ______________________________________                                         .sup.1. At Room Temperature                                              

Although the present invention has been described with reference to thespecific details of particular embodiments thereof, it is not intendedthat such details be regarded upon the scope of the invention exceptinsofar as to the extent that they are included in the accompanyingclaims.

I claim:
 1. A naphthopyran represented by the following graphic formula: ##STR14## wherein I. L is the group, --W--T(Z)=Xg, wherein(a) W is selected from the group consisting of the bivalent radicals, ##STR15## said J and J' each being selected from the group consisting of C₁ -C₄ alkyl, or J and J' taken together is a single oxygen, (b) T is selected from the group consisting of carbon and sulfur, (c) X is selected from the group consisting of oxygen, sulfur and --N--J", said J" being selected from the group hydrogen, hydroxy, C₁ -C₄ alkyl, C₁ -C₄ alkoxy or C₁ -C₄ alkenyl, or J" may combine with Z to form a pyridyl group (d) Z is selected from the group consisting of hydrogen, C₁ -C₄ alkyl, C₁ -C₄ alkenyl, C₁ -C₄ monohaloalkyl, C₁ -C₄ alkoxy(C₁ --C₄)alkyl, amino, C₁ -C₄ mono- or di-alkylamino, the unsubstituted and substituted aryl groups phenyl and naphthyl, and the unsubstituted and substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl furfuryl, the aryl and heterocyclic substituents being selected from the group consisting of C₁ -C₄ alkyl, C₁ -C₄ monohaloalkyl, C₁ -C₄ polyhaloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₁ -C₄ alkoxy and halogen, said halogen (or halo group) being fluorine or chlorine, and (e) g is the integer 1 or 2 when X is sulfur and is the integer 1 when X is oxygen or --N--J", and II. B and B' are each selected from the group consisting of:(a) the unsubstituted or substituted aryl groups phenyl and naphthyl, (b) the unsubstituted or substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl and furfuryl, (c) C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₃ -C₆ cycloalkyl, C₁ -C₄ alkoxy(C₃ -C₆) cycloalkyl, and halo C₃ -C₆ cycloalkyl, said halo group being fluorine or chlorine, and (d) B and B' may combine and taken together form the group, adamantylidene, the aryl group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, the heterocyclic group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, said halogen (or halo group) being fluorine or chlorine.
 2. A naphthopyran represented by the following graphic formula: ##STR16## wherein, I. L is the group, --W--T(Z)=Xg, wherein:(a) W is selected from the group consisting of oxygen, carbon and nitrogen, (b) T is carbon, (c) X is oxygen, (d) Z is selected from the group consisting of C₁ -C₄ alkyl, C₁ -C₄ monoalkylamino and phenyl, and (e) g is the integer 1, and II. B and B' are each selected from the group consisting of:(a) the unsubstituted or substituted aryl groups phenyl and naphthyl, (b) the unsubstituted or substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl and furfuryl, (c) C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₃ -C₆ cycloalkyl, C₁ -C₄ alkoxy(C₃ -C₆) cycloalkyl, and halo C₃ -C₆ cycloalkyl, said halo group being fluorine or chlorine, and (d) B and B' may combine and taken together form the group, adamantylidene, the aryl group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, the heterocyclic group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ (C₁ -C₄)alkyl and halogen, said halogen (or halo group) being fluorine or chlorine.
 3. The naphthopyran of claim 2 wherein W is oxygen, Z is methyl, phenyl or methylamino.
 4. The naphthopyran of claim 1 wherein L is acetoxy, benzoyloxy or methyl carbamyloxy.
 5. The naphthopyran of claim 2 wherein B and B' are each selected from the group consisting of phenyl and substituted phenyl.
 6. The naphthopyran of claim 5 wherein the substituted phenyl is mono- or di(C₁ -C₄)alkylphenyl, mono- or di-(C₁ -C₄)alkoxyphenyl, chlorophenyl or fluorophenyl.
 7. The naphthopyran of claim 3 wherein B and B' are each selected from the group consisting of phenyl and substituted phenyl.
 8. The naphthopyran of claim 7 wherein the substituted phenyl is mono- or di(C₁ -C₄)alkylphenyl, mono- or di-(C₁ -C₄)alkoxyphenyl, chlorophenyl and fluorophenyl.
 9. The naphthopyran of claim 4 wherein B and B' are each selected from the group consisting of phenyl and substituted phenyl, said substituted phenyl being selected from mono- or di-(C₁ -C₄)alkylphenyl, mono- or di(C₁ -C₄)alkoxyphenyl, chlorophenyl or fluorophenyl.
 10. 5-acetoxy-3(3,4-dimethoxyphenyl),3(2-fluorophenyl)-3H-naphtho[2,1-b]pyran.
 11. 5-methylcarbamoyloxy-3(3,4-dimethoxyphenyl),3(2-fluorophenyl)-3H-naphtho[2,1-b]pyran.
 12. 5-acetoxy-3,(4-methoxyphenyl),3(2-fluorophenyl)-3H-naphtho[2,1-b]pyran.
 13. 5-acetoxy-3(3,4-dimethoxyphenyl)-3-phenyl-3H-naphtho[2,1-b]-pyran.
 14. 5-acetoxy-3,3(4-methylphenyl)-3H-naphtho[2,1-b]pyran.
 15. A photochromic article comprising a polymerized organic host material and a photochromic amount of a naphthopyran compound represented by the following graphic formula: ##STR17## wherein, I. L is the group, --W--T(Z)=Xg, wherein:(a) W is selected from the group consisting of the bivalent radicals, ##STR18## said J and J' being selected from the group consisting of C₁ -C₄ alkyl, or J and J' taken together is a single oxygen, (b) T is selected from the group consisting of carbon and sulfur, (c) X is selected from the group consisting of oxygen, sulfur and -N-J", said J" being selected from the group hydrogen, hydroxy, C₁ -C₄ alkyl, C₁ -C₄ alkoxy or C₁ -C₄ alkenyl, or J" may combine with Z to form pyridyl group, (d) Z is selected from the group consisting of hydrogen, C₁ -C₄ alkyl, C₁ -C₄ alkenyl, C₁ -C₄ monohaloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, amino, C₁ -C₄ mono- or di-alkylamino, the unsubstituted and substituted aryl groups phenyl and naphthyl, and the unsubstituted and substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl furfuryl, the aryl and heterocyclic substituents being selected from the group consisting of C₁ -C₄ alkyl, C₁ -C₄ monohaloalkyl, C₁ -C₄ polyhaloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₁ -C₄ alkoxy and halogen, said halogen (or halo group) being fluorine or chlorine, and (e) g is the integer 1 or 2 when X is sulfur and is the integer 1 when X is oxygen or --N--J", and II. B and B' are each selected from the group consisting of:(a) the unsubstituted or substituted aryl groups phenyl and naphthyl, (b) the unsubstituted or substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl and furfuryl, (c) C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy (C₁ -C₄)alkyl, C₃ -C₆ cycloalkyl, C₁ -C₄ alkoxy(C₃ -C₆) cycloalkyl, and halo C₃ -C₆ cycloalkyl, said halo group being fluorine or chlorine, and (d) B and B' may combine and taken together form the group, adamantylidene, the aryl group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, the heterocyclic group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, said halogen (or halo group) being fluorine or chlorine.
 16. The photochromic article of claim 15 wherein the organic host material is selected from the group consisting of polymers of polyol(allyl carbonate) monomer, polyacrylates, poly(alkylacrylates), polymers of polyfunctional acrylate monomers, cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinylidene chloride), polycarbonate, polyurethanes, poly(ethylene terephthalate), polystyrene, copoly(styrene-methylmethacrylate), copoly(styrene-acrylonitrile), polyvinylbutyral, and polymers of diallylidene pentaerythritol.
 17. A photochromic article comprising a polymerized organic host material and a photochromic amount of a naphthopyran compound represented by the following graphic formula: ##STR19## wherein I. L is the group, --W--T(Z)=Xg, wherein:(a) W is selected from the group consisting of oxygen, carbon and nitrogen, (b) T is carbon, (c) X is oxygen, (d) Z is selected from the group consisting of C₁ -C₄ alkyl, C₁ -C₄ monoalkylamino and phenyl, and (e) g is the integer 1, and II. B and B' are each selected from the group consisting of:(a) the unsubstituted or substituted aryl groups phenyl and naphthyl, (b) the unsubstituted or substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl and furfuryl, (c) C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₃ -C₆ cycloalkyl, C₁ -C₄ alkoxy(C₃ -C₆) cycloalkyl, and halo C₃ -C₆ cycloalkyl, said halo group being fluorine or chlorine, and (d) B and B' may combine and taken together form the group, adamantylidene, the aryl group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, the heterocyclic group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, said halogen (or halo group) being fluorine or chlorine, and said organic host material is selected from the group consisting of polymers of polyol(allyl carbonate) monomer, polyacrylates, poly(alkylacrylates), polymers of polyfunctional acrylate monomers, cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinylidene chloride), polycarbonate, polyurethanes, poly(ethylene terephthalate), polystyrene, copoly(styrene-methylmethacrylate), copoly(styrene-acrylonitrile), polyvinylbutyral, and polymers of diallyidene pentaerythritol.
 18. The photochromic article of claim 16 wherein L is acetoxy, benzoyloxy or methyl carbamyloxy.
 19. The photochromic article of claim 17 wherein B and B' are each selected from the group consisting of phenyl and substituted phenyl, said substituted phenyl being selected from mono- or di-(C₁ -C₄)alkylphenyl, mono- or di(C₁ -C₄)alkoxyphenyl, chlorophenyl or fluorophenyl.
 20. The photochromic article of claim 19 wherein the organic host material is a solid transparent homopolymer or copolymer of diethylene glycol bis(allyl carbonate), poly(4,4'-dioxydiphenyl-2,2-propane), polymethylmethacrylate, or polyvinylbutyral.
 21. The photochromic article of claim 20 wherein the photochromic compound is present in an amount of from about 0.01 to 20 weight percent.
 22. The photochromic article of claim 21 wherein the article is a lens.
 23. A photochromic article comprising a solid transparent polymerized organic host material and a photochromic amount of each of (a) a first photochromic substance selected from the group consisting of spiro(indolino) naphthoxazines, spiro(indolino) pyrido benzoxazines, and spiro(indolino) benzoxazines, and (b) a naphthopyran compound represented by the following graphic formula: ##STR20## wherein, I. L is the group, --W--T(Z)=Xg, wherein:(a) W is selected from the group consisting of the bivalent radicals, ##STR21## said J and J' each being selected from the group consisting of C₁ -Chd alkyl, or J and J' taken together is a single oxygen, (b) T is selected from the group consisting of carbon and sulfur, (c) X is selected from the group consisting of oxygen, sulfur and --N--J", said J" being selected from the group hydrogen, hydroxy, C₁ -C₄ alkyl, C₁ -C₄ alkoxy or C₁ -C₄ alkenyl, or J" may combine with Z to form a pyridyl group, (d) Z is selected from the group consisting of hydrogen, C₁ -C₄ alkyl, C₁ -C₄ alkenyl, C₁ -C₄ monohaloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, amino, C₁ -C₄ mono- or di-alkylamino, the unsubstituted and substituted aryl groups phenyl and naphthyl, and the unsubstituted and substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl furfuryl, the aryl and heterocyclic substituents being selected from the group consisting of C₁ -C₄ alkyl, C₁ -C₄ monohaloalkyl, C₁ -C₄ polyhaloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₁ -C₄ alkoxy and halogen, said halogen (or halo group) being fluorine or chlorine, and (e) g is the integer 1 or 2 when X is sulfur and is the integer 1 when X is oxygen or --N--J", and II. B and B' are each selected from the group consisting of:(a) the unsubstituted or substituted aryl groups phenyl and naphthyl, (b) the unsubstituted or substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl and furfuryl, (c) C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₃ -C₆ cycloalkyl, C₁ -C₄ alkoxy(C₃ -C₆) cycloalkyl, and halo C₃ -C₆ cycloalkyl, said halo group being fluorine or chlorine, and (d) B and B' may combine and taken together form the group, adamantylidene, the aryl group substituents C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, the heterocyclic group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, said halogen (or halo group) being fluorine or chlorine.
 24. The photochromic article of claim 23 wherein the organic host material is selected from the group consisting of polymers of polyol(allyl carbonate) monomer, polyacrylates, poly(alkylacrylates), polymers of polyfunctional acrylate monomers, cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinylidene chloride), polycarbonate, polyurethanes, poly(ethylene terephthalate), polystyrene, copoly(styrene-methylmethacrylate), copoly(styrene-acrylonitrile), polyvinylbutyral, and polymers of diallylidene pentaerythritol.
 25. A photochromic article comprising a solid transparent polymerized organic host material and a photochromic amount of each of (a) a first photochromic substance selected from the group consisting of spiro(indolino) naphthoxazines, spiro(indolino) pyrido benzoxazines, and spiro(indolino) benzoxazines, and (b) a naphthopyran compound represented by the following graphic formula: ##STR22## wherein, I. L is the group, --W--T(Z)=Xg, wherein:(a) W is selected from the group consisting of oxygen, carbon and nitrogen, (b) T is carbon, (c) X is oxygen, (d) Z is selected from the group consisting of C₁ -C₄ alkyl, C₁ -C₄ monoalkylamino and phenyl, (e) g is the integer 1, and II. B and B' are each selected from the group consisting of:(a) the unsubstituted or substituted aryl groups phenyl and naphthyl, (b) the unsubstituted or substituted heterocyclic groups pyridyl, thienyl, furyl, piperidinyl and furfuryl, (c) C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₃ -C₆ cycloalkyl, C₁ -C₄ alkoxy(C₃ -C₆) cycloalkyl, and halo C₃ -C₆ cycloalkyl, said halo group being fluorine or chlorine; and (d) B and B' may combine and taken together form the group, adamantylidene, the aryl group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, the heterocyclic group substituents being selected from C₁ -C₄ alkyl, C₁ -C₄ haloalkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkoxy(C₁ -C₄)alkyl and halogen, said halogen (or halo group) being fluorine or chlorine, and wherein the organic host material is selected from the group consisting of polymers of polyol(allyl carbonate)monomer, polyacrylates, poly(alkylacrylates), polymers of polyfunctional acrylate monomers, cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinylidene chloride), polycarbonate, polyurethanes, poly(ethylene terephthalate), polystyrene, copoly(styrene-methylmethacrylate), copoly(styrene-acrylonitrile), polyvinylbutyral, and polymers of diallylidene pentaerythritol.
 26. The photochromic article of claim 24 wherein L is acetoxy, benzoyloxy or methyl carbamyloxy.
 27. The photochromic article of claim 2 wherein B and B' are each selected from the group consisting of phenyl and substituted phenyl, said substituted phenyl being selected from mono- or di-(C₁ -C₄)alkylphenyl, mono- or di(C₁ -C₄)alkoxyphenyl, chlorophenyl or fluorophenyl.
 28. The photochromic article of claim 27 wherein the organic host material is a solid transparent homopolymer or copolymer of diethylene glycol bis(allyl carbonate), poly(4,4'-dioxydiphenol2,2-propane), polymethylmethacrylate, or polyvinylbutyral.
 29. The photochromic article of claim 28 wherein the first photochromic substance is a spiro(indolino) pyrido benzoxazine or spiro(indolino) naphthoxazine.
 30. The photochromic article of claim 28 wherein the first photochromic substance and photochromic naphthopyran compound are each present in amounts of from about 0.05 to about 10 weight percent.
 31. The photochromic article of claim 30 wherein the weight ratio of the first photochromic substance to the naphthopyran compound varies from about 1:3 to about 3:1.
 32. The photochromic article of claim 31 wherein the article is an ophthalmic lens. 